Glow tube



Nov. 7, 1933.

D. VON MlHALY 33,832

GLOW TUBE Filed July 2, -1929 Fig.1. 1

Patented Nov. 7,. 1933 UNITED STATES PATENT OFFICE GLOW TUBE Dnes von Mihaly, Berlin-Wilmersdorf, Germany,

assignor to Telehor Aktien Gesellschaft, Berlin-Charlottenburg, Germany Application July 2, 1929, Serial No. 375,524, and in Germany August 21, 1928 1 Claim. (Cl. 176-122) drops, the luminous glow disappears simulta-- neously practically over the whole of the surface and similarly the fighting up takes place simultaneously at all points.

If, as is the case with glow lamps of the character referred to as hitherto known, a spot is formed at the moment when the lamp is extinguished or lit up by a fighting up of the lumigg nous glow at various points, it may happen that a part of the picture assembling device, for instance a hole in the Nipkow disc through which a' picture element is to be reproduced, will pass in front of a portion of the cathode surface which remained dar whereby the reproduction would be detrimentally affected. The drawback above referred to is avoided by the present invention in which use is made of a large glowing surface, the illumination of which is uniform.

If use is made of a controlling electrode, the latter is also constructed in the form of a frame, which preferably corresponds to the shape of the anode frame.

The frames may for instance be constituted by pieces of bent wire and, if desired, be strengthened against one another by insulating members in order to maintain a definite distance between them.

The invention is illustrated by way of example in the accompanying drawing, in which Figure 1 illustrates the arrangement of the electrodes according to the invention, in perspective view, whilst Figure 2 shows a modification comprising a controlling electrode arranged between the cath- 'ode and the anode.

In the drawing, 1 is the anode, which is constituted by a simple frame of bent wire, and 2 is the cathode consisting in a known manner of a plate the contour of which corresponds to the shape of the anode frame 1.

In the modification illustrated in Figure 2, a controlling electrode 3 is arrangedbetween the anode 1 and the cathode 2, which controlling electrode is constructed in the form of a wire frame like the anode l.

Instead of making the anode and the controlling electrode of bent wire, they may be made of a stamped sheet metal frame, of this casting, or the like.

What I claim is:-

A glow tube for the reception of pictures from a distance, for talking films and the like, having a glow cathode in the form of a plate, and an 35 andde in the form of an open frame the bars thereof being all in a plane with the edges of the cathode plate.

DENIES voir many. 

